This project is concerned with the blood donations of high school students with different ethnic backgrounds. Four conditions will be compared. One group of students will receive an educational program on blood, its physiology and role in medical procedures. A second group will receive a modeling program based on cognitive-behavioral principles designed to heighten motivation to donate blood. A third group will receive both of these conditions. In addition, there will be an untreated control group. All four groups will be exposed to a biannual school blood drive. The effects of these treatments on student donations and attitudes and parental donation and attitudes will be assessed. If the study is successful in developing programs to increase blood donations, the project will have contributed to the solution of a growing medical and social problem: the gap between the supply of blood and the increasing need for it.